VDR and multiple sclerosis: Regarding the haplotype frequencies within the VDR gene, the analysis of quaternary allelic haplotypes, as presented in Table 6, revealed a significant association (CCGA, P < 0.0001) and (CTAA, P = 0.0001) for FokI, BsmI, TaqI, and ApaI SNPs with multiple sclerosis patients and controls.